When a reclaim process starts for offsite tapes, and I have a bunch of tapes that are within the threshold, does anybody know how TSM decides which volumes or files to reclaim first? When the reclamation process starts, I see a whole bunch of messages like
ANR1040I Space reclamation started for volume 500394, storage pool BACKUPOFFSITE (process number 1514).
apparently for every tape which meets the threshold. Is it going to reclaim all the files for one volume before moving on to the next? Or is it just going to start reclaiming all files on all those volumes in some arbitrary sequence?
The reason I care is that if we have limited time for reclamation and can't reclaim all the eligible volumes within that window, I'd obviously rather reclaim all the files from a few tapes and get those tapes back than reclaim some files from a bunch of tapes and get none of them fully reclaimed.
Ideally, I'd like to see TSM start with the volumes with the highest reclaimable space, which can be reclaimed most quickly. If it's not going to do that, I might want to force it by setting the reclaim threshold higher.
We're using LTO tapes for our offsite copy pools. We're currently setting the threshold at 50%, and I'm wondering if that's too low, since that requires moving 100 GB to reclaim one tape. If I set it higher, less data movement is required, but the tradeoff is that we end up with more partially filled tapes in our vault. I'm starting to think that's a reasonable tradeoff, since the lower threshold might actually mean we have less chance to get any tapes fully reclaimed.
Any thoughts?
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Matt Simpson -- OS/390 Support 219 McVey Hall -- (859) 257-2900 x300 University Of Kentucky, Lexington, KY 40506 <mailto:[EMAIL PROTECTED]> mainframe -- An obsolete device still used by thousands of obsolete companies serving billions of obsolete customers and making huge obsolete profits for their obsolete shareholders. And this year's run twice as fast as last year's.
